Mass rearing of ticks will be done to facilitate the study of other phenolic and/or chlorinated organic compounds other than 2,6-dichlorophenol which may be involved in pheromone communication. The study of the production and storage of 2,6-dichlorophenol during development and in various body organs (if any) as described above will be continued. This project will also continue to investigate precursors and possible biochemical pathways leading to synthesis of 2,6-dichlorophenol. As knowledge of these processes accumulates, consideration will be given to compounds which might antagonize pheromone synthesis. Finally, studies to develop an effective, long-lasting pheromone containing formulation which can be used to curtail tick infestations (by disruption of mating) will be continued. Efforts to isolate and identify the bont tick pheromones will be continued. Recent studies carried out in the Medical Zoology Department, Naval Medical Research Unit Number Three, Cairo, Egypt has shown that the camel tick Hyalomma dromedarii responds to 2,6-DCP. We propose to look for 2,6-DCP in extracts of this tick, and in collaboration with Dr. Galila M. Khalil, Dr. Samir A. Nada, and Dr. D. E. Sonenshine to determine whether other compounds comprise the total pheromone-mediated responses.